Growth and Seed Yield of Camelina Sativa Grown Under Varying Irrigation Rates, Harvest

Research in the Klamath Basin 2007 Annual Report

Growth and Seed Yield of Camelina sativa Grown Under Varying Irrigation Rates, Harvest Method, and Soil Types in the Klamath Basin, 2007 Richard J. Roseberg, Jim E. Smith, and Rachel A. Shuck1

Introduction As described in our 2006 annual report, the recent increase in energy prices and political instability in the Middle East has sparked renewed interest in alternative energy sources and technologies both locally and nationally. Biodiesel is an appealing transportation fuel source for many reasons: it readily substitutes for petroleum diesel, it tends to burn cleaner with fewer pollutants, it can be made from many plant-based oil sources, and it can be produced on a large or small scale. Biodiesel can be made from many oilseed crops. However, the most prolific oil producers per acre tend to be tropical or subtropical crops such as palm oil, castor, and soybean. Some temperate oilseed crops, such as sunflower, meadowfoam, and flax, have higher value end-uses than biodiesel. Therefore, much of the research on oilseeds for biodiesel in temperate regions has focused on rapeseed/canola, and more recently, another oilseed crop called camelina (Camelina sativa). Please see the separate report of canola research we conducted in 2007. Camelina is an ancient crop (grown as far back as 1000 BC) that was later used extensively as a source of edible oil as well as for oil lanterns for lighting in eastern Europe in the middle ages. Its use decreased with the advent of improved trade for olive oil from southern Europe and later the development of petroleum based oils and then electric lighting in the 20th century. Camelina is of interest for dietary reasons due to its unusually high levels of Omega-3 fatty acids. It is of interest for biodiesel production because it seems to grow well in conditions of relatively poor soil, low fertility, and low moisture availability. Its seed contains 30-40% oil by weight, but seed yields are generally less than canola under ideal growing conditions, but may be similar under more stressful conditions. Both canola and camelina have been reported to exhibit some herbicidal properties in the following crop, which could potentially reduce weed control costs in crops planted after these oilseed crops. In 2007, about 15,000 acres of camelina was grown in the US, mostly in Montana, spurred by active private company contracting activity there (Duane Johnson, 2006, pers.

1 Associate Professor, Faculty Research Assistant, and Research Technician, respectively, Klamath Basin Research and Extension Center, Klamath Falls, OR.

Acknowledgements: Seed for these trials was provided by the University of Idaho Brassica Breeding and Research program and by private seed companies.

Reference to a product or company is for specific information only and does not endorse or recommend that product or company to the exclusion of others that may be suitable. ______Klamath Basin Research and Extension Center Growth and Seed Yield of Camelina sativa Grown Under Varying Irrigation Rates, Harvest Method, and Soil Types in the Klamath Basin, 2007 Page 55 Research in the Klamath Basin 2007 Annual Report

Comm.). Interest in other parts of the PNW and other regions of the country has developed very recently.

Research Justification & Objectives We found minimal camelina research or commercialization efforts in Oregon prior to 2006. Fall-planted camelina was tested at the Columbia Basin Ag. Research Center near Pendleton in the early 1960s, with mixed results (Don Wysocki 2008, pers. comm. or CBARC REF). Two unrelated small trials were planted at the Southern Oregon Research & Extension Center near Medford and at the Hyslop Farm near Corvallis in the mid-1990s. Those two trials did not produce much useful data due to poor crop emergence, growth and yield (Richard Roseberg 2006, pers. comm., Daryl Ehrensing 2008, pers. comm.). Nationally, most of the interest in camelina has been very recent, and commercial efforts have been centered in the western region, especially Montana, under conditions of limited moisture and soil fertility. This suggests that it may do well in parts of Oregon that are less than ideal for intensive cropping. The south-central region of Oregon has irrigation water available in certain areas, and reasonably good soils over larger areas. In the Klamath Basin, camelina may have a possible fit with existing crops such as potatoes, grass and alfalfa hay, small grains, and pastures, especially in fields with less than optimal irrigation and fertility. Our first attempt to study camelina at KBREC was a small observational plot seeded in October, 2006. This proved to be too late for the crop to emerge and persist successfully over the winter. In 2007 we expanded our evaluation of camelina with spring-seeded trials. The objective of these studies were to measure the growth and seed yield of camelina as influenced by irrigation rate and harvest method, as well as comparing its growth and yield in two widely differing soil types that are important to Klamath Basin agriculture.

Procedures KBREC Site Blocks of ‘Calena’ camelina were seeded at KBREC in a Poe fine sandy loam soil following spring grain variety trials grown in 2006. The camelina blocks were seeded next to the canola experiment blocks so that we could apply two rates of irrigation to separate areas during the season. Trifluralin (Treflan®) herbicide was applied April 27, 2007 at 2.0 pint/ac (1.0 lb a.i./ac) pre-plant incorporated with roto-tiller. No additional herbicides were applied during the season. Seed was planted one quarter inch deep at the rate of 8.0 lb/ac of raw seed with a Kincaid (Kincaid Equipment Manufacturing) plot planter on May 1. The plots were 20 by 4.5 ft, (9 rows at 6-inch spacing), with a harvested area of 14.5 by 4.5 ft. All plots were fertilized with 12 lb/acre N, 12 lb/acre P2O5, 12 lb/ac K2O, and 15 lb/acre S banded at planting (applying 12-12-12-15 fertilizer at 100 lb/acre). An additional 100 lb/acre N was applied as Solution 32 on June 4 through the irrigation water. Solid-set sprinklers arranged in a 40- by 40-ft pattern were used for irrigation. The entire area was irrigated uniformly until plants were fully emerged. Due to proximity and ______Klamath Basin Research and Extension Center Growth and Seed Yield of Camelina sativa Grown Under Varying Irrigation Rates, Harvest Method, and Soil Types in the Klamath Basin, 2007 Page 56 Research in the Klamath Basin 2007 Annual Report required field layout, the camelina blocks received the same amount of irrigation as the adjacent canola plots. Thus, irrigation rate for the “wet” irrigation block was based on crop water use estimates for canola calculated from the KBREC Agricultural Meteorological (AgriMet) weather station. The “dry” irrigation block received about 5/8 the amount of irrigation applied to the “wet” block after the initial germination period. Precipitation and irrigation details are shown in Table 1. Two harvest treatments were imposed. Plots receiving the “swath” harvest method were cut with a Swift Mfg. plot swather on August 17 when approximately 1/3 of the seeds had turned brown. Seed from these plots as well as those harvested using the “direct combine” harvest treatment were combined using a Hege (Hans-Ulrich Hege) plot combine with a 4.5-ft-wide header on August 23.

LKL Site The field was an Algoma silt loam soil in a continuous grain rotation. It was flooded during the winter to replenish moisture to the entire soil profile. Blocks of the ‘Colina’ camelina were seeded on May 14, 2007 with a Kincaid plot planter, as was done at the KBREC site (above), except no fertilizer was applied at planting at the LKL site. Instead, all plots were fertilized by the grower with 50 lb N/acre shanked in as anhydrous ammonia the week before planting, followed by another 50 lb/acre N as Solution 32 applied through the irrigation water in early June. The plots were irrigated by the grower during the season with the overhead linear move system used for the entire field (several hundred acres), based on his judgment of water need for his spring wheat crop. Two harvest treatments were imposed. Plots receiving the “swath” harvest method were cut with a Swift Mfg. plot swather on September 13 when approximately 1/3 of the seeds had turned brown. Seed from these plots as well as those harvested using the “direct combine” harvest treatment were combined using a Hege (Hans-Ulrich Hege) plot combine with a 4.5-ft-wide header on September 21 as was done at the KBREC site. At both sites, data collected included lodging percent, grain yield, and plant height. Bushel weight was only measured at the KBREC site due to insufficient seed samples harvested from the LKL site. Cleaned seed samples were sent to the Brassica Breeding and Research Lab (Dr. Jack Brown) at the University of Idaho for seed oil analysis. All measured parameters were analyzed statistically using SAS® for Windows, Release 9.1 (SAS Institute, Inc.) software. Data was analyzed as a split plot design at KBREC with irrigation rate as the main plot and harvest method as the sub-plot. At the LKL site data was analyzed as a randomized complete block design with the two harvest methods as treatments. Treatment significance was based on the F test at the P=0.05 level. If this analysis indicated significant treatment effects, least significant difference (LSD) values were calculated based on the student’s t test at the 5 percent level.

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Results and Discussion Soil moisture was good during seedbed preparation, and resulting germination and stand density were good. Good availability of irrigation water and relatively few hot days during the season (only eight days with maximum temperatures above 90oF, with none over 100oF), suggest that heat and moisture stress was minimal where sufficient irrigation was applied. Lodging was not observed at either site.

KBREC Site Weed pressure was light at the KBREC site and did not seem to impact crop growth. Camelina height was quite uniform across the plots and was about 31 inches tall in the “high irrigation” plots, and about 27 inches tall in the “low irrigation” plots. Camelina was in full flower with a few seed pods forming on lower branches by June 25, and seed pods were fully formed and filled with mostly green seeds by July 23. Seed seemed to mature slightly earlier in the “low irrigation” treatment area, though not enough to require separate harvest scheduling. This maturity difference became minimal by the time of harvest. Seed yield was significantly different between the two irrigation regimes, but were not significantly different between the two harvest methods (Table 2). Seed yield in the high irrigation plots were essentially double those in the low irrigation plots. The bushel weight response was inverse to the seed yield response, as bushel weight was significantly different between harvest methods, but not between irrigation treatments. Swathing resulted in larger bushel weights than direct combine for both irrigation treatments, suggesting that swathing may allow harvest of fuller, denser seeds compared to direct combining. There was not a significant irrigation rate by harvest method interaction for either seed yield or bushel weight. Seed oil content was significantly different between irrigation treatments, with the seed oil in the high irrigation rate plots slightly more than 2% greater than comparable low irrigation rate plots. There was not a significant difference in seed oil content due to harvest method, nor was there an irrigation rate by harvest method interaction. The oil yield of the high irrigation rate plots was significantly greater than that of the low irrigation rate plots, not surprising given the beneficial effect of irrigation on both seed yield and seed oil content. There was not a significant effect of harvest method on oil yield, nor was there a significant irrigation rate by harvest method interaction.

LKL Site Weed pressure was initially light at the LKL site, but moderate weed pressure did occur later in the season, possibly reducing yields at that site. Camelina height was quite uniform across the plots and was about 24 inches. Mean yield at the LKL site was 603 lb/ac, compared to 1304 lb/ac and 2677 lb/ac for low and high irrigation treatments at the KBREC site, respectively (Table 3). There was a slight tendency for greater seed yield and oil content in the plots that were direct-combined, but such differences due to harvest method were not significant. The lower yields at LKL, despite the presence of irrigation, suggest that crop growth was hampered by other factors such as weed competition.

Summary To our knowledge, 2007 was the first year camelina had been evaluated in the Klamath Basin. Despite the claims about camelina’s ability to grow and produce good seed yields under difficult conditions, it responded dramatically to irrigation in the mineral soil. The high irrigation conditions that produced greater seed yield also resulted in greater oil content in mineral soil, suggesting that camelina may respond favorably to increased inputs, at least under these conditions. Harvest method seemed to have only a small impact on yield, but perhaps a larger impact on seed size or density as measured by bushel weight. Lodging was not a problem in 2007, but weed competition, especially at the LKL site, did seem to affect growth and yield. Thus, the ultimate yield potential under various conditions in the Klamath Basin, especially in the high organic matter soils in the LKL area, has yet to be determined. The ability of camelina to compete with weeds is a question that needs to be answered, as well as the related need to develop acceptable herbicide practices.

Future Prospects Depending on camelina’s fit into existing crop rotations, it may have good potential to provide marketable quantities of oil for biodiesel or other uses in the Klamath Basin. A commercial biodiesel production facility is currently in operation near Klamath Falls, and a Willamette Valley-based company has been scouting for grower contracts in this area, but high grain prices have led growers to plant wheat and barley instead of the more speculative canola and camelina. Based on our research information, a commercial 25-acre field of camelina was grown in the Rogue Valley in 2008 without irrigation, resulting in a fairly good stand and apparent seed yield. If camelina proves to be well adapted to poorer growing conditions, such as land with marginal irrigation or lower fertility, it may be a viable oilseed crop in this region. If it can be demonstrated that it also provides rotation benefits to subsequent crops, it would also be more viable on higher value, more intensively managed crop land.

Table 1. 2007 Precipitation and irrigation for camelina variety x irrigation rate trails. Klamath Basin Research and Extension Center, Klamath Falls, OR. Wet Block Dry Block Precipitation Irrigation Irrigation Irrigation Irrigation Month (inch) (inch) Applications (inch) Applications

April 0.73 0.00 0 0.00 0 May 0.24 3.78 7 3.78 7 June 0.44 5.74 6 3.01 3 July 0.57 7.14 9 4.62 6 August 0.18 3.08 3 2.24 2

Total 2.16 19.74 25 13.65 18

Table 2. 2007 Comparison of irrigation rate and harvest method for camelina planted in mineral soil (ranked by seed yield). Klamath Basin Research and Extension Center, Klamath Falls,OR. Seed Oil Harvest Yield BuWt Content Oil Yield Irrigation Rate Method (lb/ac) Rank (lb/bu) Rank (%) Rank (lb/ac) Rank

Low Swath 1216 4 52.8 2 31.1 4 378 4 Low Direct 1393 3 50.2 4 31.3 3 438 3 High Swath 2806 1 53.1 1 33.3 2 935 1 High Direct 2547 2 50.8 3 33.6 1 857 2

Mean 1990 51.7 32.3 652

LSD Irrigation(0.05) 370 NSD 0.3 123

LSD Harvest NSD 0.7 NSD NSD Method(0.05)

CV (%) 25.3 1.8 1.4 25.8

P value (Irrigation) <0.001 0.145 <0.001 <0.001

P value (Harvest 0.819 <0.001 0.158 0.883 Method)

P value (Irrigation x Harvest Method 0.236 0.669 0.969 0.260 Interaction)

Table 3. 2007 Comparison of harvest method for camelina planted in high organic matter soil. Klamath Basin Research and Extension Center, Klamath Falls,OR (ranked by seed yield). Seed Oil Yield Content Oil Yield Harvest Method (lb/ac) Rank (%) Rank (lb/ac) Rank

Swath 558 2 30.6 2 171 2 Direct 781 1 31.9 1 249 1

Mean 603 30.8 187 LSD (0.05) NSD NSD NSD CV (%) 55.2 1.5 55.4 P value 0.744 0.500 0.752

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